Toggle menu anchor replaced by a button

app/Resources/static/themes/material/css/nav.scss

@@ -31,6 +31,8 @@ nav {
     padding: 0 0.5rem;
     height: auto;
     line-height: 1;
+    background-color: transparent;
+    border: none;
   }
 }
 
@@ -122,3 +124,9 @@ nav .nav-wrapper i {
 #button_export {
   display: none;
 }
+
+@media (min-width: 993px) {
+  .button-collapse {
+    display: none;
+  }
+}